Separable container for parachute-type flare

ABSTRACT

A parachute flare in the form of a projectile or shell which is separated while in its flight trajectory from a carrier part while spinning rapidly about its axis. A tubular casing attached to the flare houses a main parachute and comprises a plurality of separable parts which are normally held together by a securing means including a relatively thin-walled annular container member. In a preferred embodiment, the plurality of casing parts are all secured at an end thereof to a disc-shaped member by means of an encircling sleeve having an inwardly disposed edge portion fitting into an annular recess on the disc-shaped member. Bevel-shaped pins passing through the sleeve and into the plurality of parts are held in position by the container member. When the latter member is moved longitudinally to free the pins, such pins are removed as a result of the longitudinal forces acting upon the bevelled surfaces of the pins, thereby permitting removal of the disc-shaped member so that the plurality of parts forming the tubular casing can then be separated by centrifugal force.

ilnited States Patent 1191 1111 3,863,569

Simmons 1 Feb. 4, 1975 SEPARABLE CONTAINER FOR Primary ExaminerR0bert F. Stahl PARACHUTE-TYPE FLARE Attorney, Agent, or Firm-Pollock, Philpitt & Vande Sande [75] Inventor: Bjorn Herman Olof Simmons,

Karlskoga, Sweden [73] Assignee: Aktiebolaget Bofors, Bofors, Sweden [57] ABSTRACT v A parachute flare in the form of a projectile or shell [22] Flledf June 1972 which is separated while in its flight trajectory from a [21] Appl. No 259,985 carrier part while spinning rapidly about its axis. A tubular casing attached to the flare houses a main parachute and comprises a plurality of separable parts [30] Foreign Application Priority Data which are normally held together by a securing means June 11, Sweden .1 including a relatively thin-walled annular container member. In a preferred embodiment, the plurality of [1.8. CI. asing parts are a ecured at an end thereof to a disc. Int- Cl. haped member means of an encircling leeve hay- 0f Search 34.4, 37.6, 49.4, ing an an 10251352 annular recess on the disc-shaped member. Bevelshaped pins passing through the sleeve and into the References Cited plurality of parts are held in position by the container UNITED STATES PATENTS member. When the latter member is moved longitudi- 1,309,982 7/1919 Darling 102/3516 y to free the Pins, Such P are removed as a 2,20l,482 5/1940 Driggs, Jr 102/35.6 sult of the longitudinal forces acting upon the bevelled 3,143,965 8/1964 La Pointe 102/4914 surfaces of the pins, thereby permitting removal of the 3,374,739 3/l968 Rodger lO2/49.4 disc-shaped member so that the plurality of parts 3,712,232 1/1973 Abel etal. 102/35.6 f i th t bular asing can then be separated by centrifugal force.

6 Claims, 3 Drawing Figures BRAKE PAFACHUTE PATENTED 41975 3,863 569 BRAKE PAFACHUTE 5 7a E1 MAINIPARACH UTE FLA-RE Fig, 1

SEPARABLE CONTAINER FOR PARACHUTE-TYPE FLARE BACKGROUND OF THE INVENTION The present invention relates to a device forming a part of a projectile or shell. The device is separable from the carrier part of the projectile or shell and comprises a charge or flare provided with a parachute, and a container which encloses one end of the charge and includes one or more side surfaces as well as a member enclosing said parachute. In its longitudinal direction the container is divided into a number of parts, which are secured to the charge by means of securing members also forming a part of the container so that when the container is blown off the carrier part, the action of the securing members ceases and the parts are thrown to the side in relation to the continued path of the charge by the centrifugal force resulting from the rapid spinning of the projectile or shell about its longitudinal axis.

Said device is used, inter alia, in illuminating projectiles, in which the charge consists ofa pyrotechnical luminous composition, or flare, and in which the construction of the unit is intended to cause the flare to be ignited only a predetermined time after the unit has been separated from the projectile carrier, so that during this time it will be possible to brake the movement of the unit both along and around its axis of symmetry, so that economic ignition of the flare will be obtained. The braking of the movements of the unit along the axis of symmetry usually takes place by means of a brake or drogue parachute attached to the unit, while the braking of the movements around the axis of symmetry is achieved with brake flaps or similar means. The delayed ignition is achieved by allowing the expelling charge which causes the separation of the unit from the projectile also to initiate a delay charge attached to the container which, after its delay time, in turn initiates a separating charge. The latter change separates the container from the other parts of the unit, and at such time the aforementioned securing means releases the ends of the parts which enclose the parachute. These and the parts can then be thrown to the side by the centrifugal force, and release the main parachute for the flare, while the other ends of the parts are held together by a ring or a corresponding means which permits said ejection. The main parachute can thus be opened, after which the ignited flare can slowly descend to the ground, suspended in its parachute.

It has hitherto been proposed to make the securing members for the container parts in such a way that, to secure the parts axially, the ends of the parts of the tubular member have had cleats or corresponding means directed inwardly towards the axis of symmetry of the unit, with such cleats being engaged in corresponding recesses in the flare or in members applied to the flare, while the radical locking radially of the parts has been achieved with the container, which holds the cleats engaged in said recesses. Such securing members can be used for projectiles with low or medium rates of spin, but for projectiles with high rates of spin, e.g. 13,000 rpm. and more, it has proved that the container, in order to withstand the centrifugal forces arising in the container must be made of such thick material that it takes up more of the space in the projectile injected for the payload than can be accepted. It might be mentioned that the radial forces are approximately twice as great at 13,000 rpm. than as at 9,000 rpm.

SUMMARY OF THE INVENTION The purpose of the present invention is primarily to solve this problem so as to permit the use of thin material in the container. In addition to the fact that, by making the container with thin walls, the space in the projectile can be utilized efficiently, the container will be just as cheap and economical to manufacture as for projectiles with low and medium rates of spin, while it does not need to be provided with any special reinforcements or made of any special material.

The feature that can mainly be considered to characterize the device according to the invention is that the securing members include an attachment which is resistant to the radial forces arising in the unit and which encloses the usually tubular member enclosing the main parachute, and in that the position and/or the possible fastening of the attachment in the parts will be actuated to achieve the release of the parts by the axial forces occurring in the unit as a result of its spinning when the container is blown away.

BRIEF DESCRIPTION OF THE DRAWINGS Embodiments suggested at present which have the properties significant for the invention will be described in the following, with reference to the attached drawings, in which FIG. 1 shows, in a vertical view, a cross-section of a first embodiment of the device applied to a partly shown unit that can be expelled from a projectile;

FIG. 2 shows, in a corresponding way, a vertical view and cross-section of a second embodiment and;

FIG. 3 shows, in a way corresponding to FIG. 1, a vertical view and cross-section of a third embodiment.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT In FIG. 1, there are shown only those parts of a unit that are expelled from the carrier of a projectile. In FIG. 1, the reference character 1 illustrates a tubular member or casing which is formed of a number of separableparts so that each part, in its secured position, will be parallel with the axis of symmetry 2 of the unit. The ends 1a of the parts 1 are secured to a disc-shaped part 3, which in a suitable manner is fastened to a flare 4, and a main parachute is stored in a space 5 inside the multi-part tubular container. 1 Outside the ends 1a of the parts 1, a sleeve 6 is affixed, which sleeve is resistant to the centrifugal forces in the unit caused by its spinning about axis 2.

Normally the parts I are kept attached to the flare 4 by'an edge 6a of the sleeve 6 which is turned inwardly towards the axis of symmetry 2 and engages in a corresponding recess in the part 3. The sleeve 6 is then also fastened to the parts 1 by means of pins 7 or the like which extend inwardly from the sleeve with oblique surfaces 7a into the parts 1. The pins or corresponding devices are kept in place by the container 8, which thus need be dimensioned only to resist the centrifugal force acting on said pins.

When the container 8, by means of a separating charge not shown, is separated from the unit, the pins will thus be released, and because of their oblique surfaces 7a will be pressed outwardly by the axial forces arising in the flare 4 and parts comprising the tubular member I, which are achieved by means of a brake or drogue parachute fastened to the parts, which strives to brake the unit longitudinally, to subsequently provide for economic ignition of the flare. The pins 7 have become disengaged, the parts 1 can now be separated from the other elements in the unit and particularly from the encircling and restraining sleeve 6. The various parts of the device can then be thrown to the side in relation to the continued path of the flare.

FIG. 2, shows an alternative embodiment of the device according to the invention in which pins 7 of corresponding means are utilized. Instead of the sleeve 6 and the disc-shaped part 3, the securing members comprise an element 9 fastened to the flare 4, which has a flange-like edge 90 extending in the longitudinal direction of the unit, inside of which edge the ends Ia are located. As will be noted from FIG. 2, the parts 1 are turned in so that they are located inside the edge 9a. The element 9 is also fastened to the flare 4, as well as to the parts, by means of said pins 7, which extend in from the flange-formed edge of the parts with the above-mentioned oblique surfaces. The container 8 is located outside of the element 9 and keeps the pins 7 in place. In this case also the pins are released when the container is blown away, after which the pins can be pressed out by the axial forces.

Instead of influencing the fastening of the securing means (the sleeve 6 and the element 9) the position of the securing means can be influenced so as to produce the same result. The device according to FIG. 3 is intended to show an example of this. In this case, the securing means comprises of a ring 10 which can be displaced axially between two end positions. In one of these end positions (i.e. the position according to FIG. 3) it is held in place by the container, e.g. by a turnedin part 8a, and in a similar way as described above it encloses the end la of the parts 1 of the tubular member. In the other end position, to which it is moved by the above-mentioned axial forces arising in the unit, ring 10 releases the ends la so that the parts 1 can be released, as described above, from the flare. In this case the parts 1 are detachably secured to a part 11 which is fastened in the flare, and the parts 1 at one end have a cleat 1c turned inwards which engages in a corresponding recess in the part 11. The cleat can, of course, be located on the part II and the recess in the parts I. The part I] also has a space or recess Ila intended for the ring when this in its other end position, and in order to facilitate the axial displacement of the ring it is ap propriate to make it with an oblique surface 10a. In addition to the turned-in part 8a, the container can have cleats, a flange, or corresponding means at its outer end, which will ensure that the container will pull the ring towards its other end position when it is blown away.

The invention is not limited to the embodiments shown above as examples, but can also be subject to modifications within the scope of the following claims. Thus, for instance, a part of the flare itself can replace the part 11, and the flare is then made with the necessary corresponding recess for the cleat or edge 10, and with a space or recess corresponding to the space 11a.

1 claim:

1. In a parachute-type flare adapted to be fired in a trajectory with a high rate of spin and including a means which is separated from a carrier part, with said means including a pyrotechnic flare portion and a tubular casing formed of a plurality of separable casing parts detachably secured to the flare portion and housing a parachute, the improvement in means for detachably securing said casing parts to said flare portion comprising:

means including a disc-shaped portion attached to said flare portion and an annular ring portion encircling the ends of said casing parts lying adjacent said disc-shaped portion.

means engaging said ring portion to normally restrain said ring portion against longitudinal movement so as to maintain said ring portion in its said encircling position preventing radial outward movement of said casing parts in response to centrifugal forces,

an annular container normally encircling said ring portion,

said engaging means being responsive to removal of said annular container from its normal encircling portion to permit longitudinal movement of said ring portion relative to said casing parts to thereby free said casing parts for outward radial movement.

2. The improvement of claim I wherein said engaging means comprising a plurality of pins passing through said annular ring portion and into said casing parts, said pins having bevelled end portions.

3. The improvement of claim I wherein said engaging means comprises an annular protuberance on said annular container frictionally engaging an annular recess on said annular ring portion.

4. In a parachute-type flare adapted to be fired in a trajectory with a high rate of spin and including a means which is separated from a carrier part, with said means including a pyrotechnic flare portion and a tubular casing formed of a plurality of separable casing parts which is detachably secured to the flare portion and houses a parachute, the improvement in means for detachably securing said casing parts to said flare portion comprising:

a disc-shaped member attached to said flare portion,

a ring portion which encircles the ends of said casing parts lying adjacent said disc-shaped member,

a plurality of pins each having a bevelled end and passing radially inwardly through said ring portion and into a respective casing part,

and an annular container member surrounding said ring portion to retain said pins in place,

whereby upon removal of said annular container member and the application of a longitudinally acting force tending to separate said casing from said flare portion said pins are expelled to thereby permit the said ends of said casing parts to be freed of the restraining action of said ring portion so that said casing parts can be separated by centrifugal force to render said parachute operative.

5. The improvement of claim 1 wherein said ring portion is separate from said disc-shaped member and includes an inturned annular edge portion which engages with an annular recess formed in said disc-shaped member.

6. The improvement of claim 1 wherein said ring portion is integral with and forms an upstanding rim of said 

1. In a parachute-type flare adapted to be fired in a trajectory with a high rate of spin and including a means which is separated from a carrier part, with said means including a pyrotechnic flare portion and a tubular casing formed of a pLurality of separable casing parts detachably secured to the flare portion and housing a parachute, the improvement in means for detachably securing said casing parts to said flare portion comprising: means including a disc-shaped portion attached to said flare portion and an annular ring portion encircling the ends of said casing parts lying adjacent said disc-shaped portion. means engaging said ring portion to normally restrain said ring portion against longitudinal movement so as to maintain said ring portion in its said encircling position preventing radial outward movement of said casing parts in response to centrifugal forces, an annular container normally encircling said ring portion, said engaging means being responsive to removal of said annular container from its normal encircling portion to permit longitudinal movement of said ring portion relative to said casing parts to thereby free said casing parts for outward radial movement.
 2. The improvement of claim 1 wherein said engaging means comprising a plurality of pins passing through said annular ring portion and into said casing parts, said pins having bevelled end portions.
 3. The improvement of claim 1 wherein said engaging means comprises an annular protuberance on said annular container frictionally engaging an annular recess on said annular ring portion.
 4. In a parachute-type flare adapted to be fired in a trajectory with a high rate of spin and including a means which is separated from a carrier part, with said means including a pyrotechnic flare portion and a tubular casing formed of a plurality of separable casing parts which is detachably secured to the flare portion and houses a parachute, the improvement in means for detachably securing said casing parts to said flare portion comprising: a disc-shaped member attached to said flare portion, a ring portion which encircles the ends of said casing parts lying adjacent said disc-shaped member, a plurality of pins each having a bevelled end and passing radially inwardly through said ring portion and into a respective casing part, and an annular container member surrounding said ring portion to retain said pins in place, whereby upon removal of said annular container member and the application of a longitudinally acting force tending to separate said casing from said flare portion said pins are expelled to thereby permit the said ends of said casing parts to be freed of the restraining action of said ring portion so that said casing parts can be separated by centrifugal force to render said parachute operative.
 5. The improvement of claim 1 wherein said ring portion is separate from said disc-shaped member and includes an inturned annular edge portion which engages with an annular recess formed in said disc-shaped member.
 6. The improvement of claim 1 wherein said ring portion is integral with and forms an upstanding rim of said disc-shaped member. 